Four point planing type of speed boat hull



g 28, 19152 H. D. CANAZZI 3,051,115

FOUR POINT PLANING TYPE OF SPEED BOAT HULL Filed July 19, 1960 J 6 1;;92 1g9. 2228 f 7% L q I 1 6 2 @611 25 14 s l r 117 $24 ?%263127 25 v ENTOR P] Q. 7. mpg/Donald Canaggj, L P 1 BY a 1Q 3b 1F 3,051,115 Patented Aug. 28, 1962 inc 3,051,115 FOUR POINT PLANING 'IYPE OF SPEED BBAT HULL Henry Donald Canazzi, 178 Jewett Parkway, Buffalo, N.Y. Filed July 19, 1960, Ser. No. 43,944 8 Claims. (131. 114-56) My invention relates to speed boat bulls and more particularly to improvements in the type of hull shown in my Patent 2,900,945 issued August 25, 1959.

After extensive tests of the hull shown in the above noted patent it has been found that while said hull meets the desired top speed and stability at all forward speeds it does not bank particularly well on turns, especially high speed turns and as a result when such turns are made an action known as tripping may occur, and such action unless immediately overcome by reducing the speed and the curvature of the turn may cause the hull to overturn.

An object of the present invention is to provide an improved speed boat hull of the type shown in Patent 2,900,945 which will have the desired top speed and stability and which will be safely maneuverable at all speeds.

Another object is to provide such a hull with a plurality of bottom surfaces including a central tunnel extending from its bow to its stern end and predeterminately curved longitudinally and transversely for directing water and air therethrough and imparting a predetermined lift to the hull, a pair of outwardly and upwardly inclined primary non-trip surfaces each adjoining the outer side of one planing surface, a pair of outwardly and upwardly inclined secondary non-trip and spray rail forming surfaces each adjoining the outer side of one primary nontn'p surface and one side wall of the hull, and to form and arrange said surfaces to allow the hull to bank toward the inner side of a turn path and thereby prevent any tripping action tending to overturn the hull.

Another object is to provide each planing surface intermediate its ends with an inwardly offset transverse step dividing it into fore-and-aft planing sections, whereby at slow planing speeds the hull planes on the entire area of said sections and as the planing speed increases planes on decreasing rear areas of said sections, thereby reducing the wetted area of said sections to obtain and maintain a higher top speed from a given propulsive force.

Another object is to provide each of the primary and secondary non-trip surfaces and the adjacent side Wall with a transverse step formed to establish communication with the associated planing surface step and thereby prevent the latter from creating a forward motion retarding vacuum effect and thereby causing air to lubricate the rear planing sections.

Another object is to provide the inner side of each planing surface step with a fin formed and arranged to control the escape of air and Water pressure from the tunnel.

Another object is to provide an improved hull of the character described wherein the longitudinal plane of each bow portion is arranged to coincide with the longitudinal center of one planing surface and the forward end portion of each planing surface is equally reduced transversely to smoothly merge into its bow portion thereby to reduce the resistance of the hull to forward motion through water.

Another object is to provide the bow portion of the tunnel with a plurality of angularly related steps spaced, formed and arranged to resist fore-and-aft oscillations of the hull.

These and other objects and characteristics of the improved hull of the present inventions will appear from a perusal the following detailed description and the drawings wherein like reference numerals designate like parts.

In the drawings:

FIG. 1 is a side elevational view of an improved boat hull constructed in accordance with the principles of my present invention.

FIG. 2 is a bottom plan view thereof.

FIG. 3 is a front elevational view thereof.

FIG. 4 is a rear elevational view thereof.

FIG. 5 is an enlarged transverse sectional view taken about on the line 5--5 of FIG. 1.

FIG. 6 is a similar transverse sectional view taken about on the line 66 of FIG. 1, and

FIG. 7 is a fragmentary horizontal sectional View taken about on the line '77 of FIG. 1.

In order to accomplish the objects of my present invention, a hull constructed in accordance with the principles of said invention has each of its pair of spaced bow portions inwardly spaced from its side surfaces and alined with the medial plane of one of its pair of spaced planing surfaces so that a pair of outwardly and upwardly inclined primary non-trip surfaces, each adjoining the outer side of one how portion and one planing surface and a pair of outwardly and upwardly inclined secondary non-trip spray rail forming surfaces each adjoining the outer side of one primary non-trip surface and one side surface of the hull are formed and arranged to allow the hull to readily bank toward the inner side of a turn path and thereby prevent any tripping action tending to overturn the hull.

The thus located pair of planing surfaces intermediate their bow and stern ends are each also formed with a transversely disposed step providing the planing surfaces with separated fore-and-aft sections whereby at planing speeds the hull planes on the fore-and-aft sections and as the speed increases, the hull planes on decreasing rear areas of said sections, thereby reducing the area of the wetted surfaces of said sections and increases the possible top speed obtainable from and maintainable by a given amount of propulsive force.

Referring now to the drawings, a presently preferred form of hull is generally designated by the numeral 10. The hull 10 is of a generally rectangular shape and has its bottom 11 between its sides 12 and between its how 13 and its stern 14 formed with a central tunnel 15 flanked by a spaced pair of upright parallel bow stems 16 and by a spaced pair of parallel planing surfaces 17, each flanked by one of a pair of spaced primary nontrip surfaces 18, each in turn flanked by one of a pair of spaced secondary non-trip surfaces 19.

The Wall of the tunnel 15, as indicated by broken lines in FIG. 1, is formed with a longitudinal curvature which progressively increases from the stern 14 to the how 13 and as shown in FIGS. 4-6 is formed with a transverse curvature which also progressively increases from the stem to the how so that the area defined by the how end of the tunnel is considerably greater than the area defined by its stern end.

As best seen in FIG. 2, the bow stems 16 are each spaced inwardly from one side 12 of the hull and are each alined with the longitudinal center of one of the spaced planing surfaces 17, which are also each spaced inwardly from one side of the hull. The planing surfaces 17, being substantially flat and of relatively small area extend from the stern 14 forwardly in parallel relation for approximately /4 of the length of the hull and each have their forward end portions progressively reduced in width to smoothly merge into one of the bow stems. The inner sides of the bow stems 16 and the planing surfaces 17 thus define the sides of the tunnel 15 and it will be apparent that Water displaced into and forced through the tunnel during forward motions of the hull will exert a continuous lifting effect on the tunnel wall until the hull is thus lifted into a planing attitude. This water lifting effect causes the hull to plane at lower speeds and while it diminishes as the hull approaches its planing attitude the pressure of air trapped in the tunnel has increased proportionately and in passing through the tunnel exerts a continuous lifting effect on the tunnel wall sufiicient to maintain the hull in its planing attitude as long as planing speed is maintained.

Another less apparent advantage of thus forming the tunnel 17 to utilize the lifting effect of displaced water and air so that the hull will plane more quickly and require less power to maintain its planing attitudes is that the displaced water and air being discharged from the stem end of the tunnel is relatively quiet and allows the hull to be successfully driven by a single outboard motor without cavitation.

The primary non-trip surfaces 18 extend from the stern 14 to the bow 13, as shown in FIGS. 1 and 2, and each adjoin and extend outwardly and upwardly from the outer side of one of the planing surfaces 17, as shown in FIGS. 46. The forward end portion of each surface 18 is also gradually reduced and smoothly merged into the outer side of the associated stem 16. The outer marginal portion of each primary surface 18 is preferably formed with a narrow coextensive angularly related flat portion 21 which is slightly inclined outwardly and downwardly thereby to better deflect water displaced by the surface '18 away from the hull.

The secondary non-trip surfaces 19 extend from the stem 14 forwardly for approximately three quarters of the length of the hull and each being slightly transversely curved inwardly adjoin and extend outwardly and upwardly from the outer edge of one of the primary surfaces 18 and each adjoin one of the sides 12 as shown in FIGS. 4-6. The juncture of each surface 19 with one side 12 is formed rib-like as at 22, whereby the secondary non-trip surface 19 also acts as a spray shedding rail.

Thus locating and forming the bottom surfaces of the hull 10, particularly the primary and secondary non-trip surfaces 18 and 19, provides a hull which at all speeds has a tripping preventing banking action toward the inner side of a turn path so that tight turns may be safely made at high speeds. This tripping preventing banking action occurs during turns in the following manner:

Assuming that the hull 1G is moving forward at a high speed and a left turn, for example, is being made, it will be understood that the rear portion of the hull will naturally tend to swing outwardly or toward the right as viewed in FIG. 4 so that the right side non-trip surfaces '18 and 19, due to their outward and upward inclination ride up the wall of water being displaced thereby and thereby cause the hull to tilt or bank toward the inner side of the left turn path. Since the left side non-trip surfaces 18 and 19 are opposite hand duplicates of the right side surfaces 18 and 19 it will be obvious that during a right turn the hull will tilt or bank toward the inner side of the right turn path.

-In order that the-hull may attain and maintain a higher top speed from a given propulsive force each planing surface 17 intermediate its fore-and-aft ends is formed with an upwardly offset transverse step portion '23, which, being formed as shown, divides it into a forward planing section 24 and a rearward planing section 25. A forward upright rearwardly facing wall 26 of the step portion 23 having a height in the order of one and one-half inches (l /2) and a rearwardly and downwardly inclined wall 27 adjoining the top of the wall 26 and the forward end of the rear planing section 25 and having a length in the order of twenty-one inches provides a suitable step.

When the hull 10 is planing the steps 23 tend to create a forward motion retarding vacuum effect which is overcome by simply venting each step 23 to atmosphere. A presently preferred manner of venting the steps 23 or allowing the flow of air thereinto is to provide each of the surfaces 18 and 19 and the sides 12 with the respective steps 28, 29 and 30 which being formed as shown in FIGS. 1, 6 and 7, communicate with each other and with one of the steps 23 and which are shaped, formed and arranged to enhance the appearance of the hull.

At lower planing speeds the hull 119 planes on the entire area of the planing sections 24 and 25 and as the planing speed increases planes on decreasing areas of said sections until the top speed is attained at which time the hull planes on four relatively small rear areas of the sections 24 and 25. It will be obvious that by thus reducing the wetted area of the sections '24 and 25 the hull 10 will attain and maintain a higher top speed from a given amount of propulsive force than would be possible with larger wetted surface areas.

Since the desired planing performance of the hull 10 requires that the steps 23 be vented to atmosphere and that a predetermined air pressure he constantly exerted against the wall of the tunnel 15, a dam or keeper fin 31 is formed and arranged between each outer side of the tunnel 15 and the inner side of each step 23 in the mannershown in FlGS. 2 and 6 and since the bottom edge of the fins 31 lie in the plane of the sections 24 and 25 they complete the sides of the tunnel in the step areas and prevent or control lateral escape of air from the tunnel. In the event it is desired to maintain a different predetermined air pressure in the tunnel 15 the length, height and shape of the fins 31 may be differently proportioned in my prior Patent 2,900,945 the tunnel wall was formed with a continuous series of spaced angularly related rearwardly facing V-shaped steps and the bow end was formed with a transverse depending rib. However, it is now preferred to form only the bow portion of the tunnel 15 of the hull 10 with a plurality of spaced steps. A V-shaped foremost step 32 is formed with a rearwardly and downwardly extending surface 33 having each of its angularly related rear edges adjoined to one of an angularly related pair of upwardly and rearwardly inclined rearwardly facing walls 34 in turn adjoined to the wall of the tunnel 15. A plurality of V-shaped steps 35, of less height than the steps 32, are each formed with a rearwardly and downwardly inclined surface 36 having each of its angularly related pair of upwardly and rearwardly inclined rearwardly facing walls 37 in turn adjoined to the wall of the tunnel 15. The steps 35 are equally spaced from each other and from the step 32, as shown in FIGS. 1 and 2 so that the walls 34 and 37 resist forward motion of water and air displaced by foreand-aft oscillation of thevhull and thereby reduce such oscillation and pounding of the hull in heavy seas. The walls 34- and 37 also serve to convert the energy of forwardly moving Water and air into forward motion of the boat.

It should be understood that the herein shown and described form of improved hull is intended to exemplify the principles of my invention and that various modifications of the shape, proportions and arrangements of the bottom surfaces of the hull may be made within the scope of the appended claims wherein I claim:

1. A planing type of speed boat hull of the character described wherein the hull bottom is formed with a pair .of downwardly and rearwardly inclined upright bOW stems, each spaced inwardly from one side of thehull, a

:pair of flat planing surfaces each spaced inwardly from one side of the hull and each having its longitudinal cenprogressively increasing from the stern to the bow end, thereby to cause water and air displaced thereinto by the bow stems to flow therethrough and exert a continuous predetermined lift on the tunnel wall; a pair of outwardly and upwardly inclined primary non-trip surfaces each extended from the stern to the bow of the hull and each having its inner side adjoined to the outer side of one of the planing surfaces and to the outer side of one of the bow stems; and a pair of outwardly and upwardly inclined secondary non-trip surfaces each extending from the stern forwardly and each having its inner side adjoined to the outer side of one of the primary non-trip surfaces and its outer side adjoined to one side Wall of the hull, whereby during a turn the then outermost nontrip surfaces ride up the wall of Water being displaced thereby and cause the hull to tilt or bank toward the inner side of the turn path.

2. A planing type of speed boat hull as set forth in claim 1 wherein the sides of a forward end portion of the planing surfaces are each equally curved to adjoin and smoothly merge into one of the bow stems, thereby reducing the resistance of the hull to forward motion.

3. A planing type of speed boat hull as set forth in claim 1 wherein each planing surface intermediate its fore-and-aft ends is provided with a step formed to divide it into fore-and-aft sections, said step having a transverse upright rearwardly facing wall adjoining the fore section and a rearwardly and downwardly inclined wall adjoining the top of the upright Wall and the aft section, and an external venting means formed in the hull for venting and supplying air to the planing surface step, whereby as the forward speed of the hull increases it planes on decreasing wetted areas of its planing surfaces and such air together with such reduction in the wetted area of the planing surfaces reduces its resistance to forward motion and allows it to attain and maintain a higher top speed from a given propulsive force.

4. A planing type of speed boat hull as set forth in claim 3 wherein each external venting means includes a step formed in the primary non-trip surface to communicate with the planing surface step, a similar step formed in the secondary non-trip surface to communicate with the primary non-trip surface step, and a similar step formed in the side wall of the hull to communicate with the secondary non-trip surface step and atmosphere, said steps being formed to supply air to the planing surface step and shaped to enhance the appearance of the hull.

5. A planing type of speed boat hull as set forth in claim 3 wherein a pair of fin-like dams are each formed between the inner side of each planing surface step and one outer side of the tunnel with its bottom surface coincident with the plane of the associated fore-and-aft sections, thereby preventing water and air from freely escaping transversely from the tunnel into the steps and thereby causing such water and air to exert a predetermined lifting effect on the tunnel wall.

6. A planing type of speed boat hull as set forth in claim 1 wherein the outer side edge portion of each primary non-trip surface is formed with a narrow and downwardly inclined surface to cause outwardly displaced water to leave the hull cleanly and the side wall and the juncture between the secondary non-trip surface and the associated side wall is formed as a rib to act as a spray shedding rail.

7. A planing type of speed boat hull as set forth in claim 1 wherein the bow portion of the tunnel is formed with a plurality of angularly related and spaced rearwardly facing shoulders to resist forward motion therein of water and air displaced by fore-and-aft oscillation of the hull, thereby reducing such oscillation and pounding of the hull in heavy seas and converting the energy of forwardly displaced water and air into forward motion of the hull.

8. A planing type of speed boat hull as set forth in claim 1 wherein the planing surfaces and the secondary non-trip surfaces extend from the stern forwardly for approximately three quarters of the length of the hull and the primary non trip surfaces each extend from the stem to the associated bow stem.

References Cited in the file of this patent UNITED STATES PATENTS 1,712,281 Royer May 7, 1929 2,900,945 Canazzi Aug. 25, 1959 2,942,282 Thompson June 28, 1960 

